Isomers are long-lived nuclear states with nuclear properties different from the corresponding ground state formed by the same numbers of protons and neutrons. They can give a key information about nuclear structure, heavy-element nucleosynthesis and limits to particle stability. High-K isomers and their decays provide opportunity to study the highspin structure especially in neutron-rich (A~190) region where protons and neutrons are in the upper regions of their respective shells (Z=50-82, N=82-126). These isomers are predicted to coexist with well-deformed collective oblate rotation . Significant contributions to this research field have already been made by GSI with the successful identification of isomers in exotic nuclei, using projectile-fragmentation reaction, A/q and Z selection in the FRS and the final isomer identification in the storage ring ESR. For instance, 183mHf, 184m2Hf and 186mHf isomers were discovered along with their excitation energies and half-life measurement . The observation of 188Hf and confirmation of previous isomers is one of goals of the new experiment at the Experimental Storage Ring at GSI. The details of the experiment and the present status of preparations will be presented. References:
 G.D. Dracoulis et al., Rep. Prog. Phys. 79(2016) 076301.
 M.W. Reed et al., Phys. Rev. C 86 (2012) 054321.